The row of letters and numbers is for the contacts on the harness as they join the PCB The numbers should be visible on the underside. It works fine for my 1984 MC924DS (with the P & J type pickups). Perhaps an inquiry from Jim under his specific topic on this site could yield more specific details or a better diagram but be patient, he's a busy man!

Leigh, I've looked a bit more into this, and opened up my bass and I'm now tending to the view that the electronics you have in your pic are non-standard and possibly not Ibanez at all. This looks like some third-party eq circuitry and the pot value of 500K is wrong for an Ibanez eq circuit. There should be 3 pots, each of 20KG type nearest the edge of the guitar. The "G" refers to an unusual taper, with a graph like an "S" on its side, and they have a centre detent. The original pots provided boost and cut of 15 or 21 dB, I'm not sure which.

As a PCB is going to be hard to find and expensive, you might consider replacing the circuitry with a different third-party set of guts, at least while you search for the PCB and the proper pots. If you follow the thread about replacement eq knobs, you might also find a source for NOS pots, but that would be between you and Yogi.

My 1984 guitar has a PCB which was a common variant, having two shorter wiring harnesses, one at each end, but as far as I know, still using the same number/letter sequence for the connections as in the diagram linked in the last posting.

This is an option....if i couldnt get the original parts id look into getting a three band bartolini bass preamp ..wire the original pick ups to it... they have one with a mid shift toggle switch which could be used in the eq on off swith position of the original bass..... i hope u can get the original stuff tho'..

if you guys dont mind, i have a few more questions. first i'd like to thank you all for being so very helpful. you guys are correct. only 3 of the 6 pots are original to the guitar (the 3 500k pots including the daul pot) the original circuit board is missing and its been replaced with a g&l pre amp. the preamp is wired to 3 new 500k pots. [IMG]http://i51.photobucket.com/albums/f382/icyuod2/IMG_8733.jpg[/IMG] [IMG]http://i51.photobucket.com/albums/f382/icyuod2/IMG_8732.jpg[/IMG] i have alot of bass guitars. lado,godin,vantage,westone,brawley,4 fenders 3 music masters-1978- one orig (with a 6 post guitar pickup-one way of preventing guys buying the cheaper short scale bass and ripping the pickup out of it for thier jazz bass guess it was an issue back in the day. 1 with a semour 1/4lbs'r still have the orig pu, and a very cool custom carved master in the works-you'd have to see it to believe it)a 1992 mb4 and the list goes on. none of these guitars use a 6 pot system. would you guys mind giving me a quick overview, of how the system works? its alot of pots, kinda makes my head spin

ok so the search is on for replacement parts. i'd like to get originals, but if i cant, what are the modern options, that will closely simulate the original tones? will i be able to use all six pot? thanks guys for all the help, you've been very helpful.

well im sure this is going to strike a sour note with some of you, but lets face it. this bass will never be a prize collectable piece. its a player.paint,tunners,bridge are too far gone to save. (pitted badly, but i have a friend thats going to replate them after alittle clean up.) serious buckel rash, chips ,dings leaking battery acid and scratches were some of the reasons i stripped the guitar. however, the polar white turned urine/tabbaco yellow, was the main reason. some real cool wood under this tacky 80's paint job. its starting to look alot like my medallion. cant wait to get it back in the spot light again. i even managed to save the ibanez logo. [IMG]http://i51.photobucket.com/albums/f382/icyuod2/IMG_8743.jpg[/IMG] [IMG]http://i51.photobucket.com/albums/f382/icyuod2/IMG_8744.jpg[/IMG]

no power tools on this puppy, i striped the clear coat with a heatgun and block sanded from there. its taking alittle longer than expected, this white paint is tough as nails. the end result will be well worth the effort.